This invention relates to hand-held slicing implements, primarily for food substances and products, and for other materials such as wood or plastic.
Slicing and related techniques such as peeling and filleting are among the most basic and important techniques in food preparation. Desserts, such as cake, and savory foods, such as tomatoes, potatoes, eggplants, meats, cheeses, and poultry, are typically sliced for consumption in raw form, prior to cooking, or subsequent to cooking. Such slicing may be performed before, during or after other operations such as rolling, stuffing, folding, etc., e.g., eggplant rollatini. For desserts, it is often necessary to slice objects such as a cake, either to level the top or to provide for multiple layers. Common examples of slicing and related techniques include halving bagels, filleting fish, butterflying veal chops, skinning salmon, peeling canteloupe, de-veining shrimp, removing the rind from cheese, leveling tortes, and layering cakes or creating other layered savory or dessert foods such as napoleons. It is important that such slices be level, even and uniform, and that the process of slicing does not deform or otherwise damage the foodstuff. A given individual slice is considered level and even when it has two surfaces which are substantially planar and parallel to each other. Slices of a group are uniform when all slices are of the same thickness. Thickness is pre-determined when one can select the thickness of the slice prior to cutting. Different prior art methods may provide for one or more of the above properties: e.g., one can easily envision an apparatus wherein all slices are level, even, and uniform, but not of pre-determined thickness (e.g., the first slice, of random thickness, would be used as a template for subsequent slicing). There are four main reasons for chefs being desirous of achieving level, even, uniform slices of pre-determined thickness.
presentation--i.e., professional, aesthetically pleasing appearance. A slice which is not of uniform thickness throughout, or a group of slices which are not all of the same thickness, appear amateurish and careless. PA1 evenness of cooking--it is usually important that the entire batch of food be sufficiently, but not overly, cooked. Internal temperature and degree of doneness are directly related to slice thickness, hence even cooking requires uniform, even slices. PA1 structural--e.g., in making eggplant rollatini, the eggplant must be thin enough to roll easily, yet not so thin as to break during cooking. When butterflying a veal chop for stuffing and subsequent barbecuing, the stuffing must not leak through either side of the veal. PA1 achievement of planned outcome--e.g., if a cake is intended to be seven layers thick, and in the oven has risen to just over three inches, a chef would need to pre-determine the thickness to be 3/8 inch. Also, if it is known that carrot slices which are 1/4 inch thick must be boiled for 1 minute to achieve a desired degree of doneness, cooking times can be planned exactly instead of estimated, and prior experience can be used.
In addition to slicing, several other cutting operations are typically performed. One is mincing, wherein using a chef's knife with the handle held between the thumb and forefinger of one hand, and the blade held near its end with the thumb and forefinger of the other hand, a rapid rocking motion minces the food to be cut into smaller and smaller morsels. Another is cutting through relatively tough, durable substances, such as frozen meat or poultry, where downward pressure must be applied on both sides of the section of blade contacting the item to be cut: not only at the handle, but also at the end of the blade. One illustrative embodiment shown here provides novel improvements over the prior art which also provides for safer and easier mincing as well as safer cutting through tough substances with less wasted effort and less pain to the hands.
The prior art provides a variety of apparati and methods for slicing, which either are inadequate in achieving their intended objective, or are overly complex, expensive, and difficult to maintain. Knives commonly found in the kitchen--such as serrated bread knives or Chef's knifes--neither guarantee that slices are level, nor even, nor uniform, nor of pre-determined thickness.
One major class of prior art knives have a guide attached at either one end or both ends of the blade. An example of a knife having a guide attached at one end is illustrated in U.S. Pat. No. 5,575,070 issued Nov. 19, 1996 to Anderson. Anderson discloses a knife with a cantilevered guide substantially the same length as the knife blade. This cutting implement includes a handle, an elongated blade, a guide adjustable with respect to the blade, and a knob substantially received in a cavity formed in the upper region of the handle. The knob protrudes from the cavity and cooperates with the guide so that a user can adjust the space between the guide and the blade by rotation of the knob.
Another example is U.S. Pat. No. 5,617,637, issued Apr. 8, 1997 to Pai. Pai discloses a sheet-like blade connected to a handle with a sharpened lower cutting edge, with an L-shaped support piece which is connected to a press piece (i.e., guide) which consists of a press seat, a horizontal upper portion, and a vertical portion perpendicular to the upper portion, and thus substantially parallel to the blade.
Other examples, wherein the guide is attached at both ends of the blade are illustrated in U.S. Pat. No. 2,301,737 issued Nov. 10, 1942 to Miller, and U.S. Pat. No. 775,601 issued Nov. 22, 1904 to Goldstein. Miller discloses a knife with a guide which attaches to both the handle and the tip. Goldstein discloses a similar knife which cooperates with a slicing board having a receiving groove.
In U.S. Pat. No. 2,358,210, issued Sep. 12, 1944, Brownsey discloses a knife with two blades, on either side of a central member which acts as a guide.
All of these prior art designs suffer from the same weaknesses. First, while the guide does in fact prevent the thickness from exceeding a certain pre-determined amount, it does nothing to prevent the slice from being less than this pre-determined thickness. Second, since the guide follows the outside of the substance being sliced, the guide essentially propagates the contour of the outside surface, thus replicating any existing curvature, waviness, or other unevenness. Third, while a knife with a guide can function, albeit subject to the above weaknesses, in vertically slicing an object such as a loaf of bread, it is not well suited to horizontally slicing an object such as a torte or cake. Finally, such knifes are poorly suited to halving an object such as a bagel, due to the difficulty of grasping the object safely while attempting to cut it.
Another prior art approach is represented by U.S. Pat. No. 4,624,166 issued Nov. 25, 1986 to Kreth et al. Such a device, commonly known among chefs as a mandoline, provides a flat bed upon which the food is moved, thus intercepting a blade offset from the surface, resulting in a slice. This approach is reasonably well suited to small food objects with sufficient stiffness, such as carrots and potatoes. However, there are a number of deficiencies with this approach as well. First, the approach does not work with delicate foodstuffs such as layer cake, which would simply deform and/or crumble when subjected to the force which would be required to attempt to slice them against the blade. Secondly, many foodstuffs such as white bread, pastries, and tomatoes, have a skin which is relatively tough with respect to their internal stiffness, such that they would merely deform, i.e., be crushed, merely by being pressed against the blade. They require a reciprocal cutting motion--as would be exercised in the use of a typical serrated knife--to be sliced without being crushed. Third, any large object such as a cake would fall apart well before it could be fully forced through such an apparatus, since the portion which has already been sliced is unsupported and deformed through the process of working its way through the slicer. Fourth, even for objects which would not fall apart, such as potatoes, the weight of the majority of the slice increasingly deforms the slice as the final part of the cut is made, creating a lip thicker than the intended slice thickness on the trailing edge of the slice once it regains its original state.
Another category of apparati for producing even, uniform slices consists of knives together with structures with regularly spaced slots or guiding edges which receive and guide a "regular" knife. An example of such a device is illustrated in U.S. Pat. No. 4,131,043, issued Dec. 26, 1978 to Colman et al. Colman discloses a food-slicing device having a food supporting cradle formed of a pair of vertically upstanding lateral wall members and an intermediate web section therebetween, the wall members diverging upwardly and outwardly from the web section, and an anvil tray extending forwardly of the leading edges of the lateral wall members and web section to receive sliced food material produced upon cutting the food in a plane closely adjacent the leading edges of the wall members and web section.
Another illustrative example is U.S. Pat. No. 3,987,541, issued Oct. 26, 1976 to Sieczkiewicz. Sieczkiewicz discloses a guide for cutting a cake into multiple layers, wherein a pair of vertically positioned walls are joined adjacent their rear edges in a generally V-shape. The walls are slanted to taper upwardly from an integral base portion to an integral top and forming an open front. The front edges of the walls are provided with spaced horizontal slots extending inwardly from their front edges. The slots in each wall are evenly spaced and are in horizontal alignment with each other whereby a knife blade can be inserted horizontally between pairs of slots to be held in a horizontal position at a pre-determined level. A cake can be turned against the knife blade to slice a horizontal layer from the top portion of the cake. The blade can then be successively lowered from slot to slot to cut the cake into a plurality of uniformly spaced layers. The main shortcoming with these designs is their complexity, wherein not only is a knife required, but also a bulky, mechanically complex auxiliary device to guide the knife. In addition, the quality of such guiding is suspect, either because the knife is only supported at one end, or because the guide only limits motion to be within one half-space, instead of a particular pre-determined cutting plane, or because the method of registering the foodstuff, i.e., incrementing its position for the next slice assures evenness of each slice, but not uniformity among slices.
Finally there are a variety of designs for professional rotary slicers, which function reasonably well but are, compared to their manual counterparts, relatively expensive, mechanically complex, and difficult to clean and otherwise maintain. They also only function well only for a limited range of foodstuffs, such as those which can be sliced thin and yet retain their structural integrity, e.g., luncheon meats and some cheeses.
Also of note is U.S. Pat. No. 3,888,005, issued Jun. 10, 1975 to Bagwell. Bagwell discloses a knife where the tip of the knife, by extending below the cutting edge of the blade, is designed to prevent the knife from scratching, abrading, or cutting a flat support surface, which is supporting an article being cut. Although suitable for this purpose, this knife is not at all useful for ensuring even, uniform slices and is noted merely because the invention disclosed here in some embodiments, in addition to ensuring even, uniform slices, has as an additional benefit the similar ability to protect the support surface.